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TR2/3/3A TR3 Oil Pressure gauge issue

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newmexTR3

newmexTR3

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Hey guys,

I've been having this ongoing problem where my oil pressure gauge is leaking at the back of the gauge. I had the gauge calibrated and tested by MOMA, and they say it is fine. I then realized that when I reinstalled it the first time I did not use the small leather washer between gauge and pressure line. I reinstalled last night with said washer and had no leaks until this morning when it started dripping all over the place.

I think there may be something else going on though- the gauge was showing abnormally high pressure- 70 at low idle and then well over 100 at speed. If that reading is true, and it should be since the gauge was recently checked out, I think the high pressure could be causing the leak. So, the question is, is there a way to adjust the overall pressure in the engine? It looks like there is some sort of adjustment nut on the oil filter housing (I have the spin-on adapter), but I've never messed with it.

If pressure is that high, this could also explain some of my oil leak problems from the pan gasket, right?

Cheers,
Gavin

ps- I heard that there is a Brit Bike & Car meet somewhere in Connecticut this weekend. Anyone going? A buddy of mine has a Norton and we were thinking of going up there.
 
The oil pressure adjustment, that screw and lockwasher on top of the oil filter housing LIMITS the oil pressure (opens up) to a maximum value. It CANNOT raise low oil pressure.

Procedure for adjusting the oil pressure relief valve:

With the engine cold, start up and run at 2000 - 2500 RPM or so. Adjust the screw until the gauge reads 70 PSI -- the factory setting. As the engine warms and oil thins, you may no longer be able to achieve 70 PSI, but that's OK. The spring/ball should open at 70 PSI limiting cold oil pressure to that figure.
 
I agree with everything above; just wanted to add that overly thick oil can also cause high oil pressure.

I used to run straight 40 weight year-round in an old, worn TR3A engine. Worked fine. But after it was rebuilt, in the winter the pressure would peg the gauge on cold starts. The pressure relief valve just wouldn't flow enough oil to keep the pressure down. Switching to a lighter weight oil for winter operation solved the problem.

Today of course I use 20W50 which should be fine down to 0F at least.
 
When do you ever see 0 Deg. F, Mr. "Sunny So. California?" :cooler:
 
After backing the adjustment screw out almost an inch, the pressure dropped down to normal levels. I can't imagine why it had been so cranked down... We'll see this weekend how the decreased pressure effects the leak i had.

Thanks for the help!
 
Result!!! Well done. Now you can drive, drive, drive! :smile:
 
newmexTR3 said:
I can't imagine why it had been so cranked down...
Click to expand...
I get the feeling that a lot of people think that turning that screw in will raise their low oil pressure. Crank, crank, crank...
 
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